L5970AD STMicroelectronics, L5970AD Datasheet
L5970AD
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L5970AD Summary of contents
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... March 2005 Figure 1. Package Table 1. Order Codes 2 The L5970AD is a step down monolithic power switching regulator with a switch current limit of 1. able to deliver more than 1A DC current to the load depending on the application conditions. The output voltage can be set from 1.235V to 35V. ...
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... L5970AD Table 2. Thermal Data Symbol R Thermal Resistance Junction to ambient th (j-amb) (*) Package mounted on board Figure 3. Pin Connection (top view) Table 3. Pin Description N. Name 1 OUT Regulator Output. 2 SYNC Master/Slave Synchronization. When it is open, a signal synchronous with the turn-off of the inter- nal power is present at the pin. When connected to an external signal at a frequency higher than the internal one, then the device is synchronized by the external signal ...
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... 4.4V to 36V CC ( 0.74V sync V = 2.33V sync I = 3mA source no load 1.65V sync 5mA REF V = 4.4V to 36V 0mA REF V = 4.4V to 36V 5mA REF L5970AD Min. Typ. Max. Unit 4 Ω 0.250 0.5 1.8 A 500 KHz 0 100 % 1.220 1.235 1. 2.7 mA µA 50 100 0 ...
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... L5970AD 3 Functional Description The main internal blocks are shown in Fig. 4, where is reported the device block diagram. They are: ● A voltage regulator that supplies the internal circuitry. From this regulator, a 3.3V reference voltage is externally available. ● A voltage monitor circuit that checks the input and internal voltages. ...
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... The frequency of the synchronization signal must be at least higher than the internal switching frequency of the device (500KHz). Figure 6. Oscillator Circuit FREQUENCY SHIFTER Ibias_osc GENERATOR D00IN1131 BIAS CLOCK RAMP GENERATOR SYNCHRONIZATOR PREREGULATOR VREG BANDGAP VREF CLOCK t RAMP SYNC L5970AD 5/11 ...
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... L5970AD 3.4 CURRENT PROTECTION The L5970AD has two current limit protections, pulse by pulse and frequency fold back. The schematic of the current limitation circuitry for the pulse by pulse protection is shown in figure 7. The output power PDMOS transistor is split in two parallel PDMOS. The smallest one has a resistor in series, R ...
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... If the INH pin is left floating, an internal pull up ensures that the voltage at the pin reaches the inhibit threshold and the device is disabled. The pin is also Vcc compatible. I CLAMP GATE DRAIN OFF ON/OFF CONTROL ON I VCC OFF PDMOS VOUT L I LOAD ESR C ON L5970AD 7/11 ...
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... Due to the fact that the internal power is a PDMOS, no boostrap capacitor is required and so, the device works prop- erly also with no load at the output. In this condition it works in burst mode, with random repetition rate of the burst. 5 Application Ideas L5970AD belongs to L597x family. Related part numbers are: ● L5970D: 1.5A (I ● ...
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... Mold flash, potrusions or gate burrs shall not exceed 0.15mm (.006inch) in total (both side). inch MIN. TYP. MAX. 0.053 0.069 0.004 0.010 0.043 0.065 0.013 0.020 0.007 0.010 0.189 0.197 0.15 0.157 0.050 0.228 0.244 0.010 0.020 0.016 0.050 0.004 OUTLINE AND MECHANICAL DATA SO-8 0016023 C L5970AD 9/11 ...
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... L5970AD 7 REVISION HISTORY Table 6. Revision History Date Revision March 2005 10/11 1 Initial load. Description of Changes ...
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